Recombined Corynebacterium glutamicum for producing L-Phe and constructing method and application thereof

Abstract

The invention discloses a recombined Corynebacterium glutamicum for producing L-Phe and a constructing method and the application thereof, and belongs to the field of metabolic engineering. In Corynebacterium glutamicum ATCC 13032, two shuttle expression vectors pEC-XK99E and pXMJ19 of the Corynebacterium glutamicum and escherichia coli are used for expressing eight key enzyme genes comprising aroF<fbr>, tktA, ppsA, aroL, pheA<fbr>, aroE, aroA and tyrB in a L-Phe synthetic route, two promoters Ptac and Plac of different intensities are used for carrying out combinational expression on the eight genes to improve the L-Phe yield, the L-Phe yield can reach as high as 5.59+ / -0.11 g / l, and accumulated shikimic acid is 0.31+ / -0.11 g / L. According to the method, over expression is achieved for the L-Phe shikimic acid key enzyme genes, and the yield of L-Phe produced by the Corynebacterium glutamicum in a fermentation mode is improved.

Description

technical field [0001] The invention relates to a recombinant corynebacterium glutamicum producing L-phenylalanine and its construction and application, belonging to the field of metabolic engineering. Background technique [0002] Phenylalanine (Phe), namely D.L-α-amino-β-phenylpropionic acid, is an aromatic heterocyclic, non-polar, electrically neutral amino acid with racemic DL-type, There are three kinds of L-type and D-type, the optical isomer with biological activity is L-phenylalanine (L-Phe), and the specific rotation is -35.1°. L-Phe can be irreversibly converted into L-tyrosine (L-Tyrosine, L-Tyr) by the coenzyme tetrahydrobiopterin in the living body, and then continue to decompose and generate a small amount of phenylpyruvate through transamination. L-Phe widely exists in nature and is one of the eight essential amino acids for human and animals, while D-Phe does not exist in nature and can only be obtained through synthetic methods. [0003] The production tec...

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Problems solved by technology

[0005] Although Escherichia coli can ferment and produce L-phenylalanine to a very high level, Escherichia coli is limited in large-scale industrial production due to its own characteristics, especially in the production of food-grade large-scale industrial production

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